Devices for sourcing 2D video data are known, for example video players like DVD players or set top boxes which provide digital video signals. The source device is to be coupled to a display device like a TV set or monitor. Image data is transferred from the source device via a suitable interface, preferably a high-speed digital interface like HDMI. Currently 3D enhanced devices for sourcing three dimensional (3D) image data are being proposed. Similarly devices for display 3D image data are being proposed.
For 3D content, such as 3D movies or TV broadcasts, additional, auxiliary graphical data may be displayed in combination with the image data, for example subtitles, a logo, a game score, a ticker tape for financial news or other announcements or news.
The document WO2008/115222 describes a system for combining text with three dimensional content. The system inserts text at the same level as the highest depth value in the 3D content. One example of 3D content is a two-dimensional image and an associated depth map. In this case, the depth value of the inserted text is adjusted to match the largest depth value of the given depth map. Another example of 3D content is a plurality of two-dimensional images and associated depth maps. In this case, the depth value of the inserted text is continuously adjusted to match the largest depth value of a given depth map. A further example of 3D content is stereoscopic content having a right eye image and a left eye image. In this case the text in one of the left eye image and right eye image is shifted to match the largest depth value in the stereoscopic image. Yet another example of 3D content is stereoscopic content having a plurality of right eye images and left eye images. In this case the text in one of the left eye images or right eye images is continuously shifted to match the largest depth value in the stereoscopic images. As a result, the system produces text combined with 3D content wherein the text does not obstruct the 3D effects in the 3D content and does not create visual fatigue when viewed by a viewer.